Improvement in bridges



ZENAS KING, OF CLEVELAND, OHIO.

, IMPROVEMENT IN BRIDGES.

Specification forming part of Letters Patent N0. 55,266, dated September25, lSb.`

To all whom t may concern Be it known that I, Z. KING, of Cleveland, inthe county of Cuyahoga and State of Ohio,

have invented certain new and useful Improvements in Bridges, being animprovement on a patent granted to P. M. Frees and myself October1,1861; and I do hereby declare that the following is a full andcomplete description of the construction ofthe same, reference being had'to the accompanying drawings, making a part of this specification, inwhich- Figure lis a side view. Fig. 2 is a top view. Fig. 3 is a view ofa portion of the under side. Fig. 4t is a transverse section in thedirection of the line a' w. Fig. 5 is an end view. Fig. 6 is a detachedsection, that will be referred to in the description.

Like letters of reference refer to like parts in the several views. l

My improvement relates to the manner of constructing bridges, ashereinafter described.

In the drawings, A represents the upper chord, and B the lower chord orstringer. To these chords are connected suspensioirrods C and braces D.

The upper chord, A, is formed of sections, the inside pieces, a a, beingof a rectangular form, as shown in Fig. 6, which is a cross-seetion ofthe chord A. These pieces abut vtogether, and the sides of the chord arelapped close to the piece a and riveted to said pieces, as shown.

It is designed to have the bridge made up of sect-ions formed of platesfirmly secured and riveted together, so as to form a span ot' anypractical length.

The cord or stringer B is composed of two pieces. The ends ofthe rods Cand braces D are flattened and riveted between these pieces, the rivetspassing through the chord, or braces and chord. The upper end of thesebraces is connected to tlie upper chord by means of an eye a', that isattached to said chord by means of the nut b, and the end of the braceshook into the eyes a., forming a hook and eye, the rods C beingconnected to the chord by means of nuts c, one above and one below thepart a of the chord, a portion of the chord being broken awayin Fig. lto show the connection.

The chord A is wider at the ends than in the center, as shown, thusgiving it more strength; or the arch may be ofthe same width at the endsas at the center. The ends abut against the footplate D', which is ofthe shape shown. 'lo the plate D' is connected the chord or Stringer Bby means of nuts d. The ends of the upper chord are curved down, asshown, and come against the foot-plate D', as stated. The two pieces ofthe stringer B part, and one passes over the side of the chord A to theplate, and the other piece passes round the other side, each terminatingin bolts E E, and is connected to said plate by nuts d, as beforestated, and shown in Fig. 3, being aview of a portion of the under side.

Between the pieces of the stringer B is a rod, B', that is united at dto the Stringer and passes along to the footplate, to which it isconnected by means of a screwnut.

The braces D, being connected by a hook and eye, allow the truss orbridge thus connected to expand'cr contract, according to the changes ofthe weather.` rIhe joints being loose, they can expand without breaking,and the nuts at the end ot' the plate D', that connect'the stringerB andbolt B', can be loosened or tightened, according to the changes oftheweather. If the chord A contracts it can be loosened by means of saidnuts, or it can be tightened, if desired; and if more tension is Adesired to be given'to the truss, it can be given by means of the nuts,and by this means the floor can be raised if it sags.

What I claim as my improvement, and desire to secure by Letters Patent,is

The chord B, with the rod B', so that the point of connection-cl' ofsaid chord and rofl,

the chord shall enter the plate D' at an angle, in combination with thecounter and main braces, thereby rendering the structure less liable tofracture, the whole being constructed as and for the purpose as hereindescribed. Witnesses: ZENAS KING.

W. E. BURRIDGE, E. E. WAITE.

